Biman Bangladesh Airlines flight BG060 was operating flights from DAC to RGN and back to DAC.
At (18:03) the Bombardier DHC-8-402 aircraft, registered (S2-AGQ) contacted Yangon control tower and at (18:16) had ILS established and reported to the Yangon control tower.
Due to adverse weather, Yangon control tower asked them to execute a go-around and the aerodrome operations was closed for the aviation safety for 2 hours.
When the weather condition got better, the aerodrome operations was opened.
Biman Bangladesh Airlines flight BG060, registered S2-AGQ made RNP approach because only localizer was available at that moment.
While the Bombardier DHC-8-402 aircraft was and making approach to runway 21, it was a bit higher than on slope 3 degree and landed on runway 21, remaining on the ground for upwards of 7 seconds.
The aircraft ran parallel to the runway, and then it flew up in the air up to 44 ft above the ground and sank again and collided with runway 03 and slid forward out of the runway and came to a complete stop on the over-run of the runway 03.
There was no fire.
All gears were collapsed and fuselage was broken into three sections.
From the evidence available, the following findings are made.
These findings should not be read as apportioning blame or liability to any particular organization or individual:
- The Indicated Air Speed (IAS) approach speed between radio altitude 536ft and 12ft was 136kts, 140kts, 144kts,150kts,154kts and 151kts respectively which are about 20kts sometime 30kts higher than 122kts air speed as per Airplane Flight Manual (AFM). The speed targeted on the CVR does not agree with the approach speed.
- While the aircraft was running parallel to the runway in four seconds, the IAS approach speed increased from 146kts to 148kts gradually which was about 26 higher than 122kts, the air speed as per Airplane Flight Manual (AFM).
While the aircraft was making approach at radio height between 14ft and 20ft, the airspeed was 149kts and 154kts respectively. At that moment the control column force difference between Captain and First Officer was maximum values +27 (Captain), and -21 (First Officer).
- While the aircraft was running parallel to the runway, it was recorded the first instance where landing gear made contact with the surface of the runway at 146kts for 0.5 second, the second instance where landing gear made contact with the surface of the runway at 148kts for 0.75 second and the third instance where the landing gear made contact with the surface at 148kts for 0.25 second respectively. Main landing gear with the ground initially at time 18:51:07 for approximately 7 secs during which several Weight On Wheels (WOW) transitions were noted. Meanwhile control column force was approximately +10 and elevator position was -2.6. The torque developed by engine 1 and engine 2 was 25% respectively.
- While the aircraft was running parallel to the runway, the Captain took control of the aircraft from the first officer. At that moment the elevator position moved from approximately -2.6 to -3.7 without an input by the crew on the control column. Consequently the aircraft suddenly flew into the air and the pilot applied the brake three times at radio altitude 1ft, 8ft and 18ft respectively. At that moment the air speed was approximately 144kts which was higher 113kts, take off speed.
- And then the aircraft flew into the air at 140kts up to radio altitude 33ft with aircraft pitch peak at 8 degree and increased to control column force +4 lb at radio altitude 44ft.
- The pilot put the propellers in beta range and reduced power lever angle (PLA) to 18 degrees and aircraft pitch change recorded from +3 to -3 degrees and collided with the surface of the runway 03. The activation of beta range would reduce the lift production of the wing significantly, and cause a nose down pitching moment that culminated in a collision with the runway surface.
- While on approach and landing phases, the pilot and copilot took turn in controlling the aircraft.
- It was observed in CVR that while the aircraft was on approach phase, at that time controlled by the first officer, the pilot reminded the copilot six times to go down.
Primary Cause While the aircraft was unstablized on approach, the pilot did not execute a go-around.